Attachment for the cutter bars of mining machines



G. c. wATsoN 2,517,267

ATTACHMENT FOR THE CUTTER BARS OF MINING MACHINES Aug. 1, 1950 3 Seets-Sheet 1 Filed March 7, 1949 Allg. l,V 1950 G, C, WATSQN 2,517,267

ATTACHMENT FOR THE CUTTER BARS OF'V MINING MACHINES Filed March 7, 1949 3 Sheets-Sheet 2 v v V g El l; E

- INVENTQR.` 650565 C /4//47500/ #waff/Vir Aug' l, 1950 G. c. WATSON 2,517,267

ATTACHMENT FOR THE CUTTER BARS OF MINING MACHINES Filed March 7, 1949 3 Sheets-Sheet 3 T ml IN1/EN TOR. @fd/962': 6I M750/y Patented Aug. 1, 1950 UNITED s'rA'n-:s PATENT or ATTACHMENT FOR THECUTTER BARS OF l MINING MACHINES George C. Watson, Denver,` Colo. Application March 7, 1949, Serial No. 80,031`

This invention` relates toa method of mining coal,`and to means for-carrying out the method. Former methods ofmining coal embodyingthe use of explosives and expandinggases have resulted in a large percentage of i fine coal or slack. This ne coal in some localities had `commercial value in pulverized coal plants, With the increasing use of gas and oil fuels, however, the market for slack coal has been depleted and the slack has become pure waste forthe mines. y

` The principal object of thisinvention is to provide amethod ofminingcoaLend means for carrying out the method which will produce a' minimum of slack and a maximum `of lump coal.

Another object of the invention is to provide an attachment for conventional oalcutting machines which will enable the same `operation of the machine to make two cuts, where before only one was possible.

A still further object is toprovide means `for breaking down and removing cut coal without the useof explosives. l

Other objects and advantages reside in the detail construction of the invention,which is `designed for simplicity, economy, and efliciency. These will become more apparent from the following description.

In the following detailed description of the invention, reference is had to the accompanying drawing which forms apart lhereof. Like numerals refer to like parts in all views of the drawing and throughout the description.

Inthe drawing:

Fig. 1 is a side View` cfa conventional coal-` cutting machine, illustrating the invention applied thereto;n

Fig.;2 is an enlarged top view,wlooklng down along the `line 2 2, Fig.` 1,.with.the coal-cutting chain employed' in the invention removed to illustrate the means for applying the improved cutter tothe conventionalmachinea i Fig. 3 is a longitudinal section,i.taken` the line 3 3, Fig. 2j I i Figs. 4, 5, Yand `6` arecrossfsectionstaken on'` the lines 4 4, 5 5, and 6 6, respectively, Fig. `3; Fig. 7 is a View of atypical coal face cut by theuse of the improved machine;

Fig. 8 is a vertical section of the coal face, taken on the line 8 8, Fig. '7;

Fig.` 9 is an enlarged, sectional view a hori zontal kerf, illustrating a coal-removing device used with the improved-method;

Fig. 10 is a similar sectionyillustrating al coalremoving device of Fig- .9;

' wherelit is clamped in place by meansof suitable soumis. (on. zee zs) Fig. 12 is a rear end view of the breaking device of Fig. 10;

Fig. 1s is a longitudinal section of the breaking' ing boom i8, cutter head i9, operators cab 2li,` `boom axle 2|, and tracks 22. Thecutter illustrated is designed for track use.

Similar cutters are used on Caterpillar and truck wheel mount-` ings for trackless mines. signed so that the boom lcanbe raised from the position of Fig. l to any desired vertical angle" about the axle 2l. It can also be rotated about the vertical axis of the turntableV I'Lto` either side" of themachine. The cutter head t9 is rotatably mounted about the longitudinal axis ofthe boom I8 so thatit may be rotated around the axis, of

theboom. The cutter head I9 usually supports a single cutter bar in the position indicated by brokenline at 23, Fig. 1. The chainfof theusual cutter bar is driven from a drive cutter chainsprocket 24.

The usual bar is supported Troma backbone bar] 25 mounted in a step plate V38on the cutter head I9.. .i a i. l

For the fpurposes of this invention, theusual cutter bar `and its cutter chain are removed from` the` machine, leaving `the backboneY barV 25 and` chain sprocket 24 in place thereon.

This invention employs a bearing frame 7264.

which is forked at its inner extremity to slide over the projecting portion of the backbone bar` 25,`

damping bolts 21. Theframe 2s and the bar 2s are maintained in axial alignment with each other by means of Cotter keys 28 slidingin key ways in bothvthe "bar` andthe frame. "Ihe` bolts 21 extend` through longitudinally slotted boltslots 29 in theyV bar 25. a,

' The frame 26 supports twoforwardly extending fork plates 30 which are welded or otherwise sef-I` cured tojthe frame 26 so as to form anintegral Vpart thereof. The frame 2Bsupports"a sprocket shaft 3| Ymountedin suitable nantifriction bearings"32`. "The sprocket shaft 3l carries atdriven` chain sprocket 33 atits middlej withinfthe con# iines'of the frame 26,` and carriesajcutterchain sprocket 34 ateach of its,extremities.`

A ldrive chain 15` is trainedebout the driven* sprocket 33 `and about the standard cutter chain sprocket 24 ofthe cutter headiil.` The `tension `thechain 35 can be `regulated*by"mearislofan` adjusting screw 36 which is threaded through the rice Such` a machine is de- 3 frame 26 into contact with the end of the backbone bar 25. After the proper adjustment has been made, the bolts 21 are tightened to retain the frame in the adj usted position.

Each of the fork plates 30 carries a step plate 31 similar to the usual step plate 38 with which conventional cutter heads |9 are provided. The step plates 31 and 384 are standard equipment and are designed to support the backbone bars 25 and the cutter bars of a conventional coal-` cutting machine.

With the present arrangement, however, two cutter bars are supported in place` of the former single bar which was mounted upon the backbone bar 25 and the step plate 38. The new double cutter bars are indicated at 39. They are slid in place over bar plates 4D which are in turn permanently mounted on the step plates 31. The bars 39 are of the usual construction and comprise two side plates spaced apart by means of runner strips 4|, against which the backs of the links of a pair of cutter chains 42 travel, as in the usual coal-cutting machine.

In this improved attachment, however, the cutter chains 42 are trained around the newly added, spaced-apart sprockets 34, and it can be readily seen that this provides two parallel, uniformly spaced cutter chains 42 at each side of the position 23 formerly occupied by the single cutter chain. It can also be seen that no changes are required in the operating mechanism of the coal cutter, since the new chains 42 are still driven from the former cutter chain drive sprocket 24 through the medium of the chain 35.

In carrying out the objects f the improved coal mining method, the two parallel cutter bars 39, with their traveling cutter chains 42, are moved horizontally across the coal face to produce a plurality of parallel, spaced-apart, horizontal kerfs 43, as shown in Figs. 7 and 8, to divide the face into spaced, horizontal layers 45 connected at the back to the unbroken face, and at the sides to the side walls or pillars of the room.

`In actual practice the chains are positioned about 18 inches apart, and the cutter bars are approximately seven feet long, so that the blocks or layers 45 measure 18 x S4 by the full width of the room. In this improved method, the blocks or layers may be broken from their anchorage at the wall and the pillars into large, easily handled blocks of`coal, and are pulled forward so that they may be handled by a loadingr machine as follows:

A plurality Iof hook plates 46, having cables 41 attached thereto, are driven back into the 'bot-- tom kerf 44 and at intermediate points, as shown in Figs. '1 and 9. The hook plates 46 are provided with outwardly extending hooks 48. Expanding devices are then forced into the kerfs at their points of connectionwith the pillars, as indicated in Fig. '7, to break the blocks loose from their side supports and allow them to fall upon the hook plates 46. The cables 41 are then drawn upon. the hooks 4,8 engagingthe blocks, to pull the blocks forwardly to a position where they .can be gathered by the loading machines.

. An expanding device for breaking the blocks loose from the wall and pillars is illustrated in Figs. 12, 13, and 14. The device comprises two hollow, inclined, wedge jaws 49 hinged together at their forward extremities upon a hinge Din D so that they may swing away from each other at their rearward extremities. A wedge member1 5| ismounted between the jaws and provided with a socketfor receiving the extremity of a drill :steel 4 52. The jaws are constantly urged together by means of suitable tension springs 53.

In use, the expanding device is pushed inwardly in the horizontal kerfs 43 until the extremity of the cut is reached, as shown in Fig. 10. `The drill steel 52 is then driven inwardly either by lhand o r through themedium of an electric or pneumatic hammer toforce the wedge member 5| forwardly, as shown in Fig'. 14. This causes the two jaws 49 to expand from each other so as to break the coal blocks from their attachment. The wedge member 5| may be locked to the extremity of the drill steel 52 by means of a cross pin 54 riding in a slotted hole 55 in the drill steel.

While a specific form of the improvement has Y l, been described and illustrated herein, it is to be understood thatlthe same may be varied, within the scope of the appended claims, without departing from rthe spirit of the invention.

Having thus described the invention, what is claimed and desired secured by Letters Patent is: 1. An attachment for coal-cutting machines having 'a cutter head carrying a chain drivev sprocket, comprising: a backbone bar extending, from said cutter head; a bearing frame slidablyv engaging said bar; a chain sprocket shaft carried by said frame; a drive sprocket on said.

sprocket shaft within said frame; a drive chain trained about said drive sprocket and -about said cutter chain sprocket; additional cutter chain sprockets mounted on the extremities of said sprocket shaft; `a coal cutter chain extending from each of the additional sprockets; and means for supporting said latter chains in parallel, spacedapart relation. y y

2. A double cutter chain attachment for coal cutting machines, comprising; :a hollow bearing frame; a sprocket shaft journalled in said bearing frame, extending through the hollow therein and projecting from both sides thereof; 'a drivel and projecting from both sides thereof; a drive sprocket on said shaft within the hollow bearing frame; a cutter bar extending from each side of said frame in parallel-relation; a cutter chain sprocket mounted on each extremity ofsaid sprocket shaft and a coal cutter chain Supported by each cutter bar and drivenfrom one cf said cutter chain "sprockets, said bearing frame havmg a receiving socket adapted to be slid over a n projecting memberl onsaid coal-cutting machine A- '1 to support said frame thereon. y GEORGE C. WATSON.

REFERENCES CITED The following references are of record in the file of this patent: l

UNITED STATES PATENTS Number Name Date 1,244,601 Hamilton oct. 30, 1917 1,304,352 Morgan 1 1 May 20, 1919 2,165,675 Pray 1 `July 11, 1939 

